I have lately been dealing with a girl who keeps calling me a hoe, and she keeps threatening to punch me (which isn't a good idea, because in a fight, I would win.)
Anyway, she keeps calling me a "hoe," but she sleeps with every guy she knows.
So, i wanted a spell that would make her fertile.
This is the tricky part
She can't know I am casting a spell on her. I cant rub her belly like in the spells I have been reading. I can, however, get a picture of her off of the internet if I need one.

If anyone knows of any fertile spells (more like a curse really, seeing as she hates children,) that I can do without her knowing or can make one that'll actually work, thatll be great!!!

You want to use a fertility spell on an enemy? Well, if you were successful, she would have a baby, probably settle down with the father, and start a family of her own, likely becoming immensely happy with her new life and the new little one. She definitely won't care about the girl she called a name. Irony, no? And fertility magick tends to be a bit "contagious" because the spirits over such magick are known for their misbehavior because they're all about abundance (not temperance). It's not at all damaging, but you may just be next in line.

It doesn't work like it does in the movies. There are still too many factors that you have not considered.

Sure...go right ahead and do a fertility spell ;)
Then go to your local bookstore and pick up a few good books on magick, and learn more.

Don't people ruin each others cars anymore? Making the other one pregnant is now a revenge thing?

I think I will do a binding spell.
Thank you to everyone who is trying to help me. And no, there is more of a reason than what I just posted. It is just the smallest tip of a huge ice berg. She has been doing a lot more than calling me names. She does stuff including threatening to physically harm me.
A demon has messaged me and is willing to become a child to be her worst enemy. I asked what he wants in return, and he said her soul.
I am considering it. However, I feel like this is going to blow up in my face and affect me more than her. I feel like as if there is a catch I don't know about. (I am willing to give her soul in return, for she has been admiring demons for the longest of time.)

If she hates kids I wouldn't do a fertility spell, not because it would be mean, but the child would be punished. She might abort it, give it up for adoption, or keep it and the child could be neglected or abused. Try ignoring her, but if it's too hard, you could cast a curse to give her bad luck or to stop her from gossiping. Avoid the fertility spell, too many things could go wrong for the child not the mother.